// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
#define CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_

#include <memory>

#include "base/macros.h"
#include "content/browser/renderer_host/event_with_latency_info.h"
#include "content/browser/renderer_host/input/tap_suppression_controller.h"
#include "content/browser/renderer_host/input/tap_suppression_controller_client.h"

namespace content {

class GestureEventQueue;

// Controls the suppression of touchscreen taps immediately following the
// dispatch of a GestureFlingCancel event.
class TouchscreenTapSuppressionController
    : public TapSuppressionControllerClient {
public:
    TouchscreenTapSuppressionController(
        GestureEventQueue* geq,
        const TapSuppressionController::Config& config);
    ~TouchscreenTapSuppressionController() override;

    // Should be called on arrival of GestureFlingCancel events.
    void GestureFlingCancel();

    // Should be called on arrival of ACK for a GestureFlingCancel event.
    // |processed| is true if the GestureFlingCancel successfully stopped a fling.
    void GestureFlingCancelAck(bool processed);

    // Should be called on arrival of any tap-related events. Returns true if the
    // caller should stop normal handling of the gesture.
    bool FilterTapEvent(const GestureEventWithLatencyInfo& event);

private:
    // TapSuppressionControllerClient implementation.
    void DropStashedTapDown() override;
    void ForwardStashedGestureEvents() override;
    void ForwardStashedTapDown() override;

    GestureEventQueue* gesture_event_queue_;

    typedef std::unique_ptr<GestureEventWithLatencyInfo> ScopedGestureEvent;
    ScopedGestureEvent stashed_tap_down_;
    ScopedGestureEvent stashed_show_press_;
    ScopedGestureEvent stashed_long_press_;

    // This is true when the stashed GestureTapDown event gets forwarded. The
    // controller should forward the next GestureTapCancel as well to maintain a
    // valid input stream.
    bool forward_next_tap_cancel_;

    // The core controller of tap suppression.
    TapSuppressionController controller_;

    DISALLOW_COPY_AND_ASSIGN(TouchscreenTapSuppressionController);
};

} // namespace content

#endif // CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCHSCREEN_TAP_SUPPRESSION_CONTROLLER_H_
